Farmers Benefit from Harvesting Solar Energy
Researchers calculate that devoting about 1 percent of U.S. farmland to agrivoltaics, the emerging practice of integrating solar installations with working farmland, would satisfy about 20 percent of present electricity demand. Agrivoltaics can reduce emissions, save water and possibly even boost crop yields.
A 2019 study from the University of Utah and Oregon State University found that the best places for solar installations tend to be the areas where we already grow food, because photovoltaic (PV) panels lose their efficiency at higher temperatures. By elevating the panels far enough above the ground, we can essentially harvest the sun twice, according to University of Arizona researcher Greg Barron-Gafford. Enough sunlight to grow crops gets past the panels, which act as a shield against extreme heat, drought and storms.
Solar panels reduce the amount of sunlight hitting the soil, “which means you have less evaporation of water,” says Barron-Gafford. He and his team were able to triple the yield of chiltepin peppers by growing them under PV panels on test plots versus unshaded control plots. Cherry tomato output doubled, and the soil on the PV plots retained 5 to 15 percent more moisture between waterings. “The plants aren’t just freeloading under the solar, they actually help the panels become more efficient,” he adds.